ANTIOCH, Calif. (KGO) -- The family of 30-year-old Angelo Quinto, a Filipino immigrant, has filed a claim against the City of Antioch for his wrongful death. They blame an illegal chokehold used by officers on the back of his neck.
"I was just hoping they could deescalate the situation," said his sister, Bella Collins. She called 911 on Dec. 23. Collins says Angelo had been experiencing mental health problems and paranoia. Quinto had been holding onto his mother, and would not let go.
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On Thursday the family's attorney showed a video, shot by his mother, showing Angelo Quinto unresponsive on the floor after family members say officers subdued him with a knee to the back of his neck. It shows Quinto bleeding from the mouth and later shows those same officers trying to revive him.
"Given what we know, a healthy young man in his mother's arms. They stuffed the life out of him," said attorney John Burris.
Quinto died three days later in the hospital without waking up. Attorneys blame asphyxiation. They're frustrated that the Antioch police have no body camera footage nor has the department named the officers involved.
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Supporters and family rallied on Thursday for more humane treatment of people in mental distress, and for a ban of that controversial chokehold.
"This is wrongful death in the sense that their conduct caused the death of this person," said Burris. "This was a healthy person before, and now his life is gone."
The Antioch Police Department did not release any new information on Thursday.
The Contra Costa District Attorney continues what it describes as an automatic and procedural investigation.
RELATED: Family says $4M settlement with Walnut Creek doesn't do 'justice,' demands non-police response to mental crisis calls
Angelo Quinto's sister, Bella, remains grief-stricken and conflicted about calling the police that night.
"I don't know if I will not feel bad. If it was the right thing to do they would not have killed my brother," said Collins.
The City of Antioch has 45 days in which to respond.
If you or a loved one are dealing with emotional distress or mental health issues, find resources and get help here.
Bay Area family files wrongful death lawsuit claiming officers used controversial chokehold that killed 30-year-old man